Multiglazing



50 air to the building.

vPatented Oct. 29, 1940 2,219,688 MULTIGLAZING Percy E. Knudsen.Pittsburgh, Pa., assignor to Pittsburgh Plate Glass Company, AlleghenyCounty, Pa.,

a corporation of Pennsylvania Application January, 1939, Serial No.252,916

Claims- The present invention relates to window construction involving aplurality of spaced sheets or panes of glass and it has particularrelation to a construction in which one of the sheets or panes 5 isremovable to admit of cleaning or othermanipulations of the glass. a

One object of the invention is to provide a multiple glazed windowconstruction which is simple and which admits of removal of one pane togive access to the interior of the construction without disturbing thesecond pane.

A second object of the invention is to provide a window construction inwhich there are no metallic parts having exposed surfaces both withinand without the building in which the construction is employed.

In order to reduce heat transmission, it has been proposed to employ aplurality of spaced sheets of glass mounted in a frame in such man- 26ner as to provide an insulative dead air space or chamber. Transmissionof heat through the windows is thus greatly reduced. However, in suchconstruction difficulty has been encountered in the provision of anadequate seal about the edges of the glass to exclude moisture from theinner space. Such moisture tended during cold weather to condense andsometimes even left a :permanent film upon the glass. It also tendedsuperficially to attack the glass to produce a haze or bloom which couldnot conveniently be removed.

.Another development of modern window constructions has involved theprovision of metallic sashes, frames and other structural elements. 35Difliculty has been experienced with them because'of high thermalconductivity. Considerable heat was transferred through them and at thesame time objectionable moisture was precipitated upon them.

The present invention involves as one feature the provisionof a windowconstruction including inner and outer panes or plates of glass, thelatter of which is clamped independently of the former, and the innersheet is so secured as to admit of 45 easy removal.

In such construction it is a simple matter to take out the removableinner glass and clean the affected surfaces without disturbing the outerglass, and thus affording access of the external As a further feature,the invention involves the provision of a window construction in whichall parts that constitute good conductors of heat are interrupted withinthe construction, thus chas visitin cold surfaces that would constitutepoints drawing in which- Figure 1 is a fragmentary elevational view of awindow constructed in accordance with the provisions of the invention.

Figure 2 is a fragmentary cross-sectional view taken substantially uponthe ure 1.

line 11-11 of Fig- 10 In the drawing like numerals refer to like partsthroughout. As shown,

a wall l 0 defines an opening in which is disposed a window constructionil, having a 15 ledge portion l2 and a shoulder l3, the latter of whichis crowned about its edge with a layer ll of cement constituting a seatfor a metallic (iron) structural bar It. The bar is preferably, ap-

proximately of T and includes outer flanges l1, inn and a connectingweb- IS. The lower edge or flange I1 is spaced slightly from theshoulder l3 and the space is packed with a suitable caulking material20, e. g. with asphalt or like bituminous 25 material mixed with afiller such as whiting.

A wooden insulative bar 22 is disposed between flanges l1 and I8 withthe upper surface thereof terminating below the upper edge of the formerflange. The bar is, also, grooved to receive the upper portion of thesecond-mentioned flange and is secured in position by means of screws 24extending through the flange l1 and terminating within the wood. Theexposed lower portion of flange I8 is covered by an insulative layer 2|of plaster or other material.-

-like cross-sectional contour, 20

er flanges l8,

Spaced sheets of glass 26 and 21 having an adhesive sealing tape orcompound 28 about-the eedges thereof are disposed upon the bar 22, withthe edges of the outer sheet (26) engaging the abutment provided by theinner face of the projecting edge of flange II. A spacer bar 29 of woodor other suitable insulative material is disposed between the sheets orplates of glass and constitutesa clamp for plate 26. It is held inposition bymeans of bolts 3|, which include heads 32 disposed insuitable sockets in the lower face of bar 22 and stem portions 33extending upwardly through openings 34 in bar 22.

The opening 36 in spacer bar 29 is offset slightly inwardly with respectto the stem 33 and preferably is downwardly tapered. Head 31 of the boltis downwardly tapered in such in the nut is screwed into position,

anner that as the bar 36 is forced slightly outwardly in order firmly togrip the edge portions of the sheet or pane 29.

The inner sheet of glass is releasably maintained in position by meansof a finish strip 38, approximately of inverted L -shapedcross-sectional outline and including a vertical branch 39, horizontalflange 4| and a downwardly-directed lip 42, the latter of which engagesthe margin of the glass 21. Member 28 is held in position upon the bar22 and actuated toward the glass 21 by means of screws 43 which arethreaded through the leg or branch 39 into suitable bushings 44 disposedin openings in bar 22. It will be manifest that the inner sheet of glass21 may be replaced by two or more spaced sheets or plates securedtogether by metallic marginal channels or like means to provide a unitthat can be installed in the same manner as a single late. p The mode ofoperation of the invention is practically self-evident from theforegoing description. It will be assumed that the metal bar I6 isdisposed in position in the opening in the wall l0 and that the bar 22is secured thereupon by means of screws 24. Sheet or plate 26 is thenpressed into position against the flange l1 and is secured fromdisplacement by means of bar 29. Plate or sheet 21 is then slid into theopening with the margins thereof engaging the inner face of said bar.Subsequently the finish strips 38 are mounted in position with the lip42 engaging the glass and the 'screws 43 are driven home in order toexert firm pressure against the edges.

An important advantage of the construction resides in the fact thatframe elements l6 can be directly mounted in the window opening duringor after the erection of the building walls. Subsequently the bars 22can be disposed. in position thereupon. Both sheet 29 and bar 29 can 1then be mounted from the interior of the building. This constitutes asubstantial advantage where the sheets are large and at considerableheight above the ground.

It will be observed that in the foregoing con-.-

45 struction. there are no metal parts extending from the exterior ofthe wall to the interior thereof.

This is an advantage because metal parts constitutes excellentconductors of heat and therefore in cold weather the inner faces ofmetal parts when exposed become chilled and are subject to condensationof moisture. Such moisture of course causes rust of the parts, andvitisunsightly and is otherwise objectionable. It will also be noted thatthe outer sheet or pane 26 is clamped by bar 29 independently of pane 21in such manner that the latter can be removed by simple release offinish strip 38 in order to admit of cleaning of the interior surfaces.

The form of invention herein shown and described constitutes a preferredform. However,

it is given primarily for purposes of illustration, and it will beapparent that numerous modifications may be made therein withoutdeparture from the spirit of the invention or the scope ofthe appendedclaims.

What I claim is:

l. A building construction embodying a wall having a window openingformed therein, metallic members providing a channel upon the marginalportions of the opening, said channel having a wide outer flange and anarrow inner flange, both flanges being vertically disposed, the

outer of the flanges projecting upwardly to provide an abutment for themargins of the outer sheet of glass, a bar of insulative material formedto flll the space between the flanges and being provided with a portionfitting over the inner flange, an outer sheet of glass having marginalportions disposed upon the bar and abutting against theupwardly-projecting margin of the outer flange, an inner sheet of glassdisposed upon the bar, a spacing member'disposed between the two sheets,a clamping plate of approxi- .glass to clamp the latter in positionindependently of the inner sheet of glass.

3. A construction as defined in claim 1 in which the spacing bar isprovided with means actuating it outwardly toward the first-mentionedsheet of glass to clamp the latter in position independently of theinner sheet of glass, said means comprising screws disposed in openingsformed in the spacing bar in eccentric relation with re spect to thescrew and a nut having a tapered head screwed upon the bolt.,

4. A window construction comprising an outer frame provided witlf aflange projecting inwardly, a sheet of glass engaging at its margin withthe flange, gripping means positively securedto the frame'andmaintaining the glass in position, a second sheet of glass secured inthe frame in spaced relation to the first. to provide a dead theconically tapered opening and a nut having a downwardly tapered headupon the screw.

5. A window construction comprising an outer frame provided with avertically disposed flange. a sheet of glass in the frame and engagingthe flange and an approximately rectangular spacing bar directly securedto the frame, means for moving the bar upon the frame to press the glassinto position against the frame, said means being operable to increaseor reduce the pressure of the bar against the glass without releasingthe latter, a second sheet of glass disposed in the frame and engagingthe bar upon the side opposite to the first-mentioned glass and means secured to the frame and actuating the secondmentioned sheet of glassagainst said bar, both of said means being operable independently ofeach other.

PERCY E. KNUDSEN.

